In 2016, Audemars Piguet introduced the frosted gold watches in their women’s Royal Oak lines, in 33 mm. and 37 mm. case sizes. The “frosted” decorative technique is the result of a collaboration between Audemars Piguet and Florentine jeweller Carolina Bucci. The signature technique involves hammering gold with a diamond-tipped tool to create minute indentations on the surface.